7 Surprising Workout Mistakes You Don't Know You're Making

Who knew that you should think about your tongue when doing sit-ups?

Busting your butt on the Stairmaster and banging out a gazillion crunches and squats isn't going to do, well, squat, if you're making these common mistakes, according to personal trainer and fitness expert Louis Coraggio.

Mistake #1: You don't think about your tongue when you do sit-ups.
We know it sounds strange, but hear us out. Women tend to use their neck muscles more than their abs when they do crunches, which is totally uncomfortable, not to mention a huge waste of time. Shift the focus back to your abdominals with this trick: Press your tongue flush against the roof of your mouth before starting your reps. It helps keep the strain off your neck so your stomach is forced to do the work.

Mistake #2:You stretch before cardio.
There's no danger in sitting on a mat and trying to touch your toes, but it's kinda boring and doesn't do much for your body. The best way to warm up your muscles and prevent injury before going on a run or jumping on the Elliptical is actually to mimic the exercise at a low level. So get on the machine you're about to use, set it at the easiest level, and exercise for about five minutes. Then start to increase the level until you're at the desired speed or difficulty. This is way better than stretching, since it gets your heart rate elevated and helps avoid burnout.

Mistake #3:You lift the same weights every time.
Many women are under the impression that using heavy weights equals bulking up, so they stick with 10 or 15-pounders and don't increase. But if you're using free weights or weight machines once or more a week, you should be slowly upping the poundage. Since your muscles build up resistance over time, aim to increase the weight by about five pounds every two or three weeks. As long as you can do 15 without feeling anything more than tiredness (as in, you're not shaking, panting, or about to pass out), you don't have to worry about ending up with arms that could star in an action flick.

Mistake #4:You do real push-ups.
Modified push-ups (where your knees are on the ground) have long been considered the lazy girl's routine. The problem is that most women have a hard time doing the knees-off-the-ground version and when they try, their form ends up suffering, making the move sort of pointless. So go on, do the modified style and ignore the smug look from the woman next to you who has her knees up. (She's probably doing them wrong anyway.) Plant your arms directly below your shoulders and keep everything from your knees to your neck in a straight line as you slowly lower yourself to the ground. Trust us, you'll still get an amazing arm workout.

Mistake #5:You prep with a pre-gym snack.
Downing an energy bar before the gym can actually zap your energy. How come? Many of those bars are high in fiber, which is normally a good thing, but it takes forever to digest. And that digestion requires energy — energy that would be better spent on your muscles. You end up feeling sluggish and having trouble pushing yourself. If you're ravenous beforehand, opt for a banana, which is digested super quickly and won't inhibit your gym time. (Just steer clear of the apples many gyms offer at the front desk — they're high in fiber too.)

Mistake #6:You overindulge afterwards.
Hey, there's nothing wrong with replenishing yourself after a strenuous sweat session — in fact, it's recommended you get some protein and carbs in your system within an hour of working out. What you don't want is to completely undo all the hard work you just put in, which is extremely common. A recent study found that people tend to overestimate the number of calories burned and underestimate the number of calories they eat. To keep yourself from eating so much that your workout becomes pointless, make sure you check the label of whatever you're eating and aim for something in the 150-calorie or under range. (In other words, not that mega-muffin at the gym cafe.)

Mistake #7:You don't weigh yourself.
You might have been told not to worry about the number on the scale or heard that weighing yourself regularly is obsessive. But the scale is actually a key tool for ditching — and keeping off — fat. Experts have found that people who weigh themselves regularly lose more weight than those who don't. It could be because we can actually see the pounds come off (motivation to keep exercising) and we also get a concrete reminder that eating unhealthily for a week straight has consequences.

Sources: Public Library of Science Journal; National Weight Control Registry

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